How to import SVG files without putting them in a new collection?
The following script is intended as a limited example tested in Blender 2.9:
create a list of current collections;
given a specified directory:
get a list of all files in that specific directory;
if the file name ends with .svg perform the import curve operation;
create a list of collections after import operation (exclude original collections);
for each collection created during the import operation:
rename the objects in the collection;
link to scene's master collection;
unlink from existing collection;
remove the collection;
import bpy
import os

dir = &quot;c:\\tmp\\svg&quot;
files = os.listdir(path=dir)
tgt_coll = bpy.context.collection # master scene collection
colls = [coll for coll in bpy.data.collections]

for f in files:
    if not f.endswith(&quot;.svg&quot;):
        continue
    bpy.ops.import_curve.svg(filepath = os.path.join(dir, f))

new_colls = [coll for coll in bpy.data.collections if coll not in colls]

for coll in new_colls:
    for obj in coll.objects:
        obj.name = coll.name # coll.name[:-4] to strip .svg
        tgt_coll.objects.link(obj)
        coll.objects.unlink(obj)
    if len(coll.objects) == 0:
        bpy.data.collections.remove(coll)